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  1. 09 9月, 2010 20 次提交
  3. 07 9月, 2010 5 次提交
  5. 24 8月, 2010 4 次提交
  7. 22 8月, 2010 2 次提交
  9. 21 8月, 2010 1 次提交
  11. 20 8月, 2010 1 次提交
  13. 18 8月, 2010 2 次提交
    • N
      tty: fix fu_list abuse · d996b62a
      由 Nick Piggin 提交于 
      tty: fix fu_list abuse

tty code abuses fu_list, which causes a bug in remount,ro handling.

If a tty device node is opened on a filesystem, then the last link to the inode
removed, the filesystem will be allowed to be remounted readonly. This is
because fs_may_remount_ro does not find the 0 link tty inode on the file sb
list (because the tty code incorrectly removed it to use for its own purpose).
This can result in a filesystem with errors after it is marked "clean".

Taking idea from Christoph's initial patch, allocate a tty private struct
at file->private_data and put our required list fields in there, linking
file and tty. This makes tty nodes behave the same way as other device nodes
and avoid meddling with the vfs, and avoids this bug.

The error handling is not trivial in the tty code, so for this bugfix, I take
the simple approach of using __GFP_NOFAIL and don't worry about memory errors.
This is not a problem because our allocator doesn't fail small allocs as a rule
anyway. So proper error handling is left as an exercise for tty hackers.

[ Arguably filesystem's device inode would ideally be divorced from the
driver's pseudo inode when it is opened, but in practice it's not clear whether
that will ever be worth implementing. ]

Cc: linux-kernel@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NNick Piggin <npiggin@kernel.dk>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      d996b62a
    • N
      fs: cleanup files_lock locking · ee2ffa0d
      由 Nick Piggin 提交于 
      fs: cleanup files_lock locking

Lock tty_files with a new spinlock, tty_files_lock; provide helpers to
manipulate the per-sb files list; unexport the files_lock spinlock.

Cc: linux-kernel@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: NAndi Kleen <ak@linux.intel.com>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NNick Piggin <npiggin@kernel.dk>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      ee2ffa0d
  15. 17 8月, 2010 3 次提交
    • G
      of: Fix missing includes · f1ca09b2
      由 Grant Likely 提交于 
      This patch fixes missing includes from a number of .c files because
the code (wrongfully) depended on prom.h including them.  The include
of linux/of_address.h was removed in microblaze prom.h in commit
"of/address: Clean up function declarations" (sha1 id 22ae782f), but
not fixed in some callers.  This patch fixes them up.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Tested-by: NMichal Simek <monstr@monstr.eu>
      f1ca09b2
    • J
      vt,console,kdb: preserve console_blanked while in kdb · beed5336
      由 Jason Wessel 提交于 
      Commit b45cfba4 (vt,console,kdb:
implement atomic console enter/leave functions) introduced the ability
to atomically change the console mode with kernel mode setting but did
not preserve the state of the console_blanked variable.

The console_blanked variable must be restored when executing the
con_debug_leave() or further kernel mode set changes (such as using
chvt X) will fail to correctly set the state of console.
Signed-off-by: NJason Wessel <jason.wessel@windriver.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
CC: Andrew Morton <akpm@linux-foundation.org>
      beed5336
    • J
      vt: fix regression warnings from KMS merge · fed891c8
      由 Jason Wessel 提交于 
      Fix the following new sparse warnings in vt.c introduced by the commit
b45cfba4 (vt,console,kdb: implement
atomic console enter/leave functions):

drivers/char/vt.c:197:5: warning: symbol 'saved_fg_console' was not declared. Should it be static?
drivers/char/vt.c:198:5: warning: symbol 'saved_last_console' was not declared. Should it be static?
drivers/char/vt.c:199:5: warning: symbol 'saved_want_console' was not declared. Should it be static?
drivers/char/vt.c:200:5: warning: symbol 'saved_vc_mode' was not declared. Should it be static?
Signed-off-by: NJason Wessel <jason.wessel@windriver.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
CC: Andrew Morton <akpm@linux-foundation.org>
      fed891c8
  17. 12 8月, 2010 1 次提交
  19. 11 8月, 2010 1 次提交
    • S
      kfifo: fix kfifo miss use of nozami.c · 4457d984
      由 Stefani Seibold 提交于 
      There are different types of a fifo which can not handled in C without a
lot of overhead.  So i decided to write the API as a set of macros, which
is the only way to do a kind of template meta programming without C++.
This macros handles the different types of fifos in a transparent way.

There are a lot of benefits:

- Compile time handling of the different fifo types
- Better performance (a save put or get of an integer does only generate
  9 assembly instructions on a x86)
- Type save
- Cleaner interface, the additional kfifo_..._rec() functions are gone
- Easier to use
- Less error prone
- Different types of fifos: it is now possible to define a int fifo or
  any other type. See below for an example.
- Smaller footprint for none byte type fifos
- No need of creating a second hidden variable, like in the old DEFINE_KFIFO

The API was not changed.

There are now real in place fifos where the data space is a part of the
structure.  The fifo needs now 20 byte plus the fifo space.  Dynamic
assigned or allocated create a little bit more code.

Most of the macros code will be optimized away and simple generate a
function call.  Only the really small one generates inline code.

Additionally you can now create fifos for any data type, not only the
"unsigned char" byte streamed fifos.

There is also a new kfifo_put and kfifo_get function, to handle a single
element in a fifo.  This macros generates inline code, which is lit bit
larger but faster.

I know that this kind of macros are very sophisticated and not easy to
maintain.  But i have all tested and it works as expected.  I analyzed the
output of the compiler and for the x86 the code is as good as hand written
assembler code.  For the byte stream fifo the generate code is exact the
same as with the current kfifo implementation.  For all other types of
fifos the code is smaller before, because the interface is easier to use.

The main goal was to provide an API which is very intuitive, save and easy
to use.  So linux will get now a powerful fifo API which provides all what
a developer needs.  This will save in the future a lot of kernel space,
since there is no need to write an own implementation.  Most of the device
driver developers need a fifo, and also deep kernel development will gain
benefit from this API.

Here are the results of the text section usage:

Example 1:
                        kfifo_put/_get  kfifo_in/out    current kfifo
dynamic allocated       0x000002a8      0x00000291      0x00000299
in place                0x00000291      0x0000026e      0x00000273

kfifo.c                 new             old
text section size       0x00000be5      0x000008b2

As you can see, kfifo_put/kfifo_get creates a little bit more code than
kfifo_in/kfifo_out, but it is much faster (the code is inline).

The code is complete hand crafted and optimized.  The text section size is
as small as possible.  You get all the fifo handling in only 3 kb.  This
includes type safe fix size records, dynamic records and DMA handling.

This should be the final version. All requested features are implemented.

Note: Most features of this API doesn't have any users.  All functions
which are not used in the next 9 months will be removed.  So, please adapt
your drivers and other sources as soon as possible to the new API and post
it.

This are the features which are currently not used in the kernel:

kfifo_to_user()
kfifo_from_user()
kfifo_dma_....() macros
kfifo_esize()
kfifo_recsize()
kfifo_put()
kfifo_get()

The fixed size record elements, exclude "unsigned char" fifo's and the
variable size records fifo's

This patch:

User of the kernel fifo should never bypass the API and directly access
the fifo structure.  Otherwise it will be very hard to maintain the API.
Signed-off-by: NStefani Seibold <stefani@seibold.net>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      4457d984